We are a publicly traded Delaware limited partnership that owns and operates crude oil and liquid petroleum transportation and storage assets in the United States of America. Our Class A common units are traded on the New York Stock Exchange (NYSE), under the symbol "EEP"
The following chart shows our organization and ownership structure as of December 31, 2017. The ownership percentages referred to below illustrate the relationships between us, Enbridge Energy Management, L.L.C., or Enbridge Management, Enbridge Energy Company, Inc., or our General Partner, and Enbridge Inc., or Enbridge, and its affiliates:
We were formed in 1991 by Enbridge Energy Company, Inc., the general partner of the Partnership (General Partner), initially to own and operate the Lakehead System, which is the United States portion of a crude oil and liquid petroleum pipeline system extending from western Canada through the upper and lower Great Lakes region of the United States to eastern Canada (Mainline System). A subsidiary of Enbridge Inc. (Enbridge) owns the Canadian portion of the Mainline system. Enbridge is the ultimate parent of our General Partner.